Investigations have been made on the use of engineering plastics, e.g. polycarbonate, as a material for hard coat. In fact, some of such plastics have been in actual use. However, bisphenol A polycarbonate is not satisfactory in hardness and has been modified to increase the hardness.
The polysilanes having phenol groups at both ends according to the present invention can be used as a starting material for producing a polycarbonate or polyester having a polysilane skeleton in the main chain. Thus, when the polysilane of the invention is used, a polycarbonate or the like with improved hardness can be prepared and a more useful material for hard coat can be provided. Further the obtained polycarbonate or the like with a polysilane skeleton has a photosensitive property and a charge-transporting property derived from the polysilane and is usable as a new type of hard coat material showing an optoelectronic function.
However, no research has been conducted on such polysilanes with phenol groups at both ends which are useful in producing a modified polycarbonate or the like. No process for preparing the polysilanes is known.
Further it is needless to say that a process was unknown for preparing such polysilanes having phenol groups at both ends wherein the degree of polymerization of polysilane is controlled and phenol groups are introduced at both ends in order to produce a modified polycarbonate or the like having properties optimal for various applications as a hard coat material.